Boysenberry Jam

Last week I drove from Fairfax down to Watsonville (six hours round trip) in search of the elusive tayberry. I found one scraggly patch of tays at an organic U-Pick farm — not enough for even one batch of jam. Rather than send me away empty handed, however, the farmer directed me to one of her neighbors, where I was able to pick nine luscious pounds of two other blackberry varieties: boysenberries and olallieberries. It was fine consolation.

When I returned home from all that driving and picking, I was so tired that I was literally swaying on my feet. I wanted to flop right over, but the boysenberries were fat, juicy, and warm from the long trip home in the car. They weren’t going to wait another day. (The oallies generously agreed to spend one night in the fridge.)

I calculated my weights and measures (three times, just to be sure) then put the simple ingredients into a big glass bowl. I was so exhausted that I felt like I’d never made jam before. I stood there staring at the gorgeous berries soaking in sugar and lemon juice, blinking hard, thinking “I must be forgetting something. This is too easy.”

But it is that easy and, man, I do think these blackberry jams are the best of all.

These are big, sweet boyz, busting with colors from maroon to deepest purple-black. Boysenberries are a triple cross — a mix of a red raspberry, a common blackberry, and a loganberry. I’m infatuated with them right now because I discovered that they were bred and born right here in California in the early twentieth century, on the farm of a man named Rudolph Boysen. They very nearly didn’t survive after Boysen’s farm was sold, but were saved and nurtured to berry fame by Walter Knott, of Knott’s Berry Farm. America’s first theme park was built on boysenberries and chicken dinners.

When it comes to blackberry-type jams, I use less sugar than many. With this recipe, you’ll really taste the berries and you’ll get a little tart with your sweet. (Oh, and if you don’t have five pounds of berries — cuz, come on, that’s a lot — but you do have three, you can click on over and use the basic recipe for Tayberry Jam. Same diff.)

Boysenberry Jam

5 pounds boysenberries
4 1/2 cups sugar
2 tablespoons lemon juice

1. Sterilize your jars and put 5 teaspoons on a plate in the freezer, to test your jam for doneness later.

2. Set aside approximately 1/4 of the berries.

3. Combine the rest of the ingredients (remaining berries, sugar, and lemon juice) in a large bowl and set them aside to macerate a while — 30 minutes to an hour at least. (Overnight in the fridge would be great, too.) You’ll know they’re ready when the berries have started to release their juice and the sugar has begun to dissolve.

4. Put the mixture into your jam pot over medium heat. Stir gently until the sugar has completely dissolved.

5. Turn up the heat and bring the mixture to a boil, stirring only as needed to prevent sticking or burning.

6. After the mixture thickens a bit, add the remaining berries. I added mine at about 15 minutes. This late addition of the berries helps your jam to have a nice texture in the end.

7. Boil the jam to the setting point, using a large, shallow, stainless-steel spoon to skim the stiff foam off the top as it cooks. This is a big batch, so it will take a while to cook. I started testing my jam for doneness at about 30 minutes and considered the jam finished at around 35 minutes. (Keep in mind that lots of factors can affect your cooking time; it may be very different for you, so be sure to watch the mixture and test it.) I prefer a faster cooking time than this and, if I were less tired, I might have split the berries into two batches — but honestly, I don’t think the flavor suffered. It’s really good.

To test your jam for doneness: Remove the pan from the heat. Use one of your frozen spoons to scoop up a little bit of jam — not a whole spoonful. Return the spoon to the freezer and wait 3 minutes. Retrieve the spoon and hold it vertically. If the mixture runs very slowly or not at all, it’s done. (Actually, if it truly doesn’t run at all — if it just sits tight and stares back at you — it’s probably overdone and you’ll have an overly firm or rubbery set. You want it to move at least a little bit on the spoon.) Alternately, give the mixture a little push with your finger. If you see creases or wrinkles, it’s done.

8. Take care of any final skimming and pour or ladle the hot jam into your sterilized jars. Wipe the jar rims and secure the lids. I processed mine for 5 minutes in a hot-water bath, which is appropriate for fruit at my elevation.

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25 Comments

I'm so with you on boysenberries. Good call on making jam because now you'll have boysenberries in the Fall, Winter, Spring… I know I've eaten them, but who knows how long ago. They are fabulous! Or at least these very ripe lovely boysenberries I ate were fabulous. We just bought a small container this past weekend, at the Fort Mason Farmers Market. They were so tasty we just sat down and ate them right then and there, unwashed and warm from the sun. I even found what resembled a little inch worm crawling on one of the berries. We saved him and then ate the berry.

I love boysenberries, ever since I lived in Portland, Or and went a-picking on Sauvie's Island. Made my first boysenberry jam, and probably last, at least for now. Also, lots of Marionberry jams. I miss all those lush blackberries.

You, my friend, are a picking fool! Good thing I had you on my side, else I woulda never got much strawberries!

I can smell that sweet jam right now. Today I'm going to pick some unknown berries, may be tayberries but they are black rather then dark red, like bigger cone shaped blackberries? Anyhow think they'll cook down nicely. Need to find out what they are before I write the labels!

We’ve grown boysenberries, my whole life! Just started making jam with them, though. I’m a little concerned, some recipes say to use pectin, some don’t. Also, my berries were frozen, and after being defrosted are in a huge pool of juice. Not sure what I should do.

Hi Tina: When I use previously frozen blackberries — or their relatives, like boysenberries — I add the sugar and lemon juice to the berries (and all of that liquid you mention) and let everything rest (macerate) in the fridge for up to 24 hours. It creates a nice even mixture that you can then cook down into jam. I don’t ever use boxed pectin for these kinds of jams, though you certainly can do that. There’s more than one right way! Hope it goes well for you. I adore boysenberries. :-)

Using this recipe, how long will the jars keep? Can I put the jars in a dark, cool area for at least six months? I recently made kumquat jalapeño marmalade and it’s good for two months and it must be refrigerated. It can also be frozen for six months.

Hi Shae,
I haven’t made jam in many years, even go rid of canning stuff. This year I really wanted to start canning again, and teach my children. So I have invested in new equipment, picked up boysenberries, and was looking for a great recipe when I found yours.
I finally got my children, ages 48 and 43 to plant gardens. Now they want to learn to preserve the things from their gardens! Oh, should say that they are men! And, they are bringing their children and friends.
Thank you so much for your help, Karen

Shae,
I did notice that some recipes for boysenberry jam don’t mention water bath and some do. I notice that you mentioned altitude, does that have something to do with it? I live at sea level. Probably best to do water bath. I can”t remember what my Mother did.
Thanks, Karen

Hi Karen: Unless they are very small batches intended to be stored in the refrigerator, all of my jam recipes call for water bath canning. That’s because water bath canning is the method approved by the National Center for Home Food Preservation for jams and jellies. They are following the guidelines of the USDA: http://nchfp.uga.edu/publications/uga/uga_processing_j_j.pdf.

That said, there are other methods of processing that are perfectly safe provided certain rules are followed. For instance, if someone were to use the inversion method (filling the jars hot and turning them over for a minute to sanitize the lid), there should be no problem so long as the jars and lids are properly prepared and the jam is jarred a temp of 185-190F. Many people also like to use the oven for sterilizing and processing. I’ll confess that I sometimes use all of these methods, but my recipes give details for water bath canning because that’s the current standard in this country.

Have a great time making jam with your family. It sounds like a lot of fun to me!

I live in OK and go to Amazon to order boysenberries. I get Oregon cans of boysenberries., whole berries in light syrup, however they are pretty mushy and there is a lot of juice. Can I use these to make this jam recipe? Do I treat the can as berries and use all the juice? One can is 15 ounces. I am at a loss. HELP!

I would love to be able to master this for my husband. Any help you could give me would be very much appreciated.

Hi Barbara: I’ve never made jam from canned fruit, but there’s no reason you shouldn’t try it. This recipe should adapt well to what you want to do, but the texture and the cooking time will probably be different — you’ll just have to cook it down to the thickness that seems right to you. If it were me, I would strain the berries, then weigh out and use just the fruit. (Use the syrup for something else.) As a test, I’d also recommend starting with a smaller batch in a smaller pot. Just reduce the amounts of sugar and lemon juice proportionally. Maybe try cutting everything in half. Let me know how it goes. :-)